1. Field of the Invention
The present invention relates in general to a simplified, low-cost air pump.
2. Description of the Related Art
An inflatable product provided with an air pump has been disclosed in many patent documents, such as U.S. Pat. No. 5,827,052, which is a previous invention of this inventor's. FIGS. 9A and 9B show an embodiment of U.S. Pat. No. 5,827,052, in which an inflatable product (5) has a built-in air pump (59). The pump body of the air pump (59) is received in the inflatable product (5). Two stiff rings are fixed on the upper end and lower end of the pump body. In operation, the user extends the air pump (59) to suck outside air into the pump body through a check valve by pulling two bands in opposite directions. Then, the user compresses the air pump (59) to push air (600) in the pump body into the inflatable product (5) through another check valve. By repeating the operations, the inflatable product (5) fills with air.
The advantages of U.S. Pat. No. 5,827,052 include: the construction of the air pump (59) is simple and low cost; the air pump (59) requires less storage volume when fully compressed.
In the present invention, this inventor further simplifies the structure of the air pump (59) so as to reduce the cost and simplify the process of producing the inflatable product. Another asset of the present invention is that forming the pump body does not require additional materials.